Guitars are one example of stringed musical instruments. Carbon fiber has been used in various portions of stringed instruments since the 1970s. In the past, the bodies of the stringed instrument have been formed of carbon fiber laminates which are generally stiff and light, however fiber laminates do not generally have the acoustic characteristics desired by those who are used to the sound of wood. The natural acoustic characteristics of carbon laminates cause the instrument to tend to sound metallic, and lack the warmth of wood. In addition, solid carbon fiber laminates have a higher density as compared to wood, and for a given weight, have significantly lower bending stiffness. Therefore using carbon fiber in the design of portions of stringed instrument in order to provide a desired acoustic response, tone, and feel of wood, is a challenge.
In the past, carbon fiber instrument builders have used continuous, long fiber reinforced materials to make the instruments. Manufacturing with these materials has been very costly, using high cost raw materials and requiring labor intensive meticulous human craftsmanship in the laminating process. This is particularly true in making the instrument sound box or body, or portion of the instrument to which the soundboard is attached, which is primarily for containing a volume of air to allow the creation of a Helmholtz resonator.
In the past, stringed musical instruments have been made from injection molded plastics. Due to the inferior structural and sonic response of these materials, these instruments are generally not preferred by most musicians.
Many different variations of wood and carbon fiber have been attempted in order to provide an acceptable level of performance with respect to vibration, structural integrity, acoustic response, tone, and feel for a stringed instrument. The use of alternative materials in the formation of sound boxes or soundboards, in many instances, has resulted in an instrument which is over damped. In addition, in many instances where carbon or other materials have been used in the formation of the soundboard or sound box, the soundboard or sound box is overly thin, causing the instrument to be prone to damage upon exposure to minor impacts.
A typical acoustic guitar has a hollow body or sound box connected to a neck. A soundboard with a sound hole is attached to the sound box. A back or bottom board is spaced from the soundboard, and a shaped side wall extends between the soundboard and backboard.
A stringed musical instrument has a series of strings strung at substantial tension from a bridge on the soundboard, across the soundboard proximate to a sound hole, and along the neck. The string tension creates forces which act on the soundboard and which, over time, may cause bending, cracking or other damage to the soundboard. The damage can result in structural failure and altered intonation of the stringed musical instrument. As such, the sound box, must be constructed in a relatively strong and stable manner, without making it to heavy, or limiting its response.
In high quality stringed musical instruments, the soundboard must be capable of vibration to provide superior acoustic performance while being rigid so that it withstands the forces created by the tensioned strings. These requirements are at cross-purposes, and have been very difficult to achieve, particularly when the soundboard is constructed from a material other than choice wooden materials.
Stringed musical instruments are also constructed so as to amplify the sound wave produced by the vibration of the strings, via a resonance body. The sound wave created by the vibrating strings is introduced into the resonance body through the bridge provided on the soundboard. Inside the resonance body, the sound wave is resounded and amplified. If the resonance body is not constructed correctly, the sound may be emitted in a muffled or dampened manner.
The present invention provides for uniformity in the construction of a stringed instrument, which in conjunction with the sound box delivers clean, brilliant sound. The construction of the stringed instrument provides for easier and more economical manufacture when state of the art equipment is used.
Generally, a relationship is present in a stringed musical instrument between the mass of the soundboard and the vibration of strings. Generally, the higher the mass of the soundboard (assuming constant stiffness), the lower the amplitude of vibration from a given string input. The lower the amplitude of vibration produced by the soundboard, the lower the volume of the instrument. Also, mass in the soundboard reduces sustain; for a higher mass, more energy is dissipated in every vibration cycle, and the string energy, soundboard vibration, and volume decrease faster resulting in less sustain.
All U.S. patents and applications all other published documents mentioned anywhere in this application are incorporated herein by reference in their entireties. Without limiting the scope of the invention in any way, the invention is briefly summarized in some of its aspects below.
The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention.